/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
 *  with the License.  You may obtain a copy of the License at
 *
 *    https://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing,
 *  software distributed under the License is distributed on an
 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 *  KIND, either express or implied.  See the License for the
 *  specific language governing permissions and limitations
 *  under the License.
 */

package org.grails.datastore.mapping.transactions;

import org.springframework.transaction.NoTransactionException;
import org.springframework.transaction.support.TransactionSynchronizationManager;

import org.grails.datastore.mapping.core.Datastore;

/**
 * Utility methods for Transactions.
 *
 * @author Graeme Rocher
 * @since 1.0
 */
public class TransactionUtils {

    public static boolean isTransactionPresent(Datastore datastore) {
        return getTransaction(datastore) != null;
    }

    public static Transaction<?> currentTransaction(Datastore datastore) {
        final Transaction<?> transaction = getTransaction(datastore);
        if (transaction == null) {
            throw new NoTransactionException("No transaction started.");
        }
        return transaction;
    }

    public static Transaction<?> getTransaction(Datastore datastore) {
        final SessionHolder sessionHolder = (SessionHolder) TransactionSynchronizationManager.getResource(datastore);
        return sessionHolder == null ? null : sessionHolder.getTransaction();
    }
}
